The body depends upon adequate blood flow. At the level of organs and tissue, blood flow is controlled by vascular smooth muscle cells. These cells line every blood vessel of the body. The contraction of these cells determines the amount of blood that flow through a certain vessel and on to organs and tissues. The contraction (and relaxation) of vascular smooth muscle cells is in turn controlled by the bioactive gas nitric oxide (NO) which is constantly produced by blood vessels. NO causes blood vessels to dilate and increases blood flow to tissues and organs. Disruption of this process leads to significant diseases, morbidity and mortality including peripheral vascular disease, ischemic heart disease, stroke and diabetes. Additionally, lack of blood flow causes tissue death and wound healing problems both during and after surgery.
Resolution of acute and chronic ischemia, be it in soft tissue flaps or skin grafts, requires restoration of tissue perfusion and blood flow. Treatments to address these factors including hyperbaric oxygen, intravenous thrombolytics, anti-inflammatory agents, and local application of angiogenesis promoters have been developed but have yielded only limited success.